<!DOCTYPE html>
<html lang="zh-CN">
<head>
  <meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1, maximum-scale=2">
<meta name="theme-color" content="#222">
<meta name="generator" content="Hexo 4.2.0">
  <link rel="apple-touch-icon" sizes="180x180" href="/xizhongren8980/images/apple-touch-icon-next.png">
  <link rel="icon" type="image/png" sizes="32x32" href="/xizhongren8980/images/favicon-32x32-next.png">
  <link rel="icon" type="image/png" sizes="16x16" href="/xizhongren8980/images/favicon-16x16-next.png">
  <link rel="mask-icon" href="/xizhongren8980/images/logo.svg" color="#222">

<link rel="stylesheet" href="/xizhongren8980/css/main.css">


<link rel="stylesheet" href="/xizhongren8980/lib/font-awesome/css/all.min.css">

<script id="hexo-configurations">
    var NexT = window.NexT || {};
    var CONFIG = {"hostname":"gitee.com","root":"/xizhongren8980/","scheme":"Gemini","version":"7.8.0","exturl":false,"sidebar":{"position":"left","display":"post","padding":18,"offset":12,"onmobile":false},"copycode":{"enable":false,"show_result":false,"style":null},"back2top":{"enable":true,"sidebar":false,"scrollpercent":false},"bookmark":{"enable":false,"color":"#222","save":"auto"},"fancybox":false,"mediumzoom":false,"lazyload":false,"pangu":false,"comments":{"style":"tabs","active":null,"storage":true,"lazyload":false,"nav":null},"algolia":{"hits":{"per_page":10},"labels":{"input_placeholder":"Search for Posts","hits_empty":"We didn't find any results for the search: ${query}","hits_stats":"${hits} results found in ${time} ms"}},"localsearch":{"enable":true,"trigger":"auto","top_n_per_article":1,"unescape":false,"preload":false},"motion":{"enable":true,"async":false,"transition":{"post_block":"fadeIn","post_header":"slideDownIn","post_body":"slideDownIn","coll_header":"slideLeftIn","sidebar":"slideUpIn"}},"path":"search.xml"};
  </script>

  <meta name="description" content="题目描述:给定一个非负整数数组，你最初位于数组的第一个位置。">
<meta property="og:type" content="article">
<meta property="og:title" content="【LeetCode】55题之跳跃游戏">
<meta property="og:url" content="https://gitee.com/xizhongren8980/xizhongren8980.git/2020/04/17/55%E9%A2%98%E4%B9%8B%E8%B7%B3%E8%B7%83%E6%B8%B8%E6%88%8F/index.html">
<meta property="og:site_name" content="一杯茶一包烟，一个BUG改一天">
<meta property="og:description" content="题目描述:给定一个非负整数数组，你最初位于数组的第一个位置。">
<meta property="og:locale" content="zh_CN">
<meta property="og:image" content="https://gitee.com/xizhongren8980/Hexo_src/raw/master/LeetCode/55_result.png">
<meta property="article:published_time" content="2020-04-17T12:22:33.604Z">
<meta property="article:modified_time" content="2020-04-17T12:22:19.853Z">
<meta property="article:author" content="MisterTian">
<meta property="article:tag" content="数组">
<meta property="article:tag" content="逆向思维">
<meta name="twitter:card" content="summary">
<meta name="twitter:image" content="https://gitee.com/xizhongren8980/Hexo_src/raw/master/LeetCode/55_result.png">

<link rel="canonical" href="https://gitee.com/xizhongren8980/xizhongren8980.git/2020/04/17/55%E9%A2%98%E4%B9%8B%E8%B7%B3%E8%B7%83%E6%B8%B8%E6%88%8F/">


<script id="page-configurations">
  // https://hexo.io/docs/variables.html
  CONFIG.page = {
    sidebar: "",
    isHome : false,
    isPost : true,
    lang   : 'zh-CN'
  };
</script>

  <title>【LeetCode】55题之跳跃游戏 | 一杯茶一包烟，一个BUG改一天</title>
  






  <noscript>
  <style>
  .use-motion .brand,
  .use-motion .menu-item,
  .sidebar-inner,
  .use-motion .post-block,
  .use-motion .pagination,
  .use-motion .comments,
  .use-motion .post-header,
  .use-motion .post-body,
  .use-motion .collection-header { opacity: initial; }

  .use-motion .site-title,
  .use-motion .site-subtitle {
    opacity: initial;
    top: initial;
  }

  .use-motion .logo-line-before i { left: initial; }
  .use-motion .logo-line-after i { right: initial; }
  </style>
</noscript>

</head>

<body itemscope itemtype="http://schema.org/WebPage">
  <div class="container use-motion">
    <div class="headband"></div>

    <header class="header" itemscope itemtype="http://schema.org/WPHeader">
      <div class="header-inner"><div class="site-brand-container">
  <div class="site-nav-toggle">
    <div class="toggle" aria-label="切换导航栏">
      <span class="toggle-line toggle-line-first"></span>
      <span class="toggle-line toggle-line-middle"></span>
      <span class="toggle-line toggle-line-last"></span>
    </div>
  </div>

  <div class="site-meta">

    <a href="/xizhongren8980/" class="brand" rel="start">
      <span class="logo-line-before"><i></i></span>
      <h1 class="site-title">一杯茶一包烟，一个BUG改一天</h1>
      <span class="logo-line-after"><i></i></span>
    </a>
      <p class="site-subtitle" itemprop="description">收藏永不停止，学习永不开始</p>
  </div>

  <div class="site-nav-right">
    <div class="toggle popup-trigger">
        <i class="fa fa-search fa-fw fa-lg"></i>
    </div>
  </div>
</div>




<nav class="site-nav">
  <ul id="menu" class="main-menu menu">
        <li class="menu-item menu-item-home">

    <a href="/xizhongren8980/" rel="section"><i class="fa fa-home fa-fw"></i>首页</a>

  </li>
        <li class="menu-item menu-item-about">

    <a href="/xizhongren8980/about/" rel="section"><i class="fa fa-user fa-fw"></i>关于</a>

  </li>
        <li class="menu-item menu-item-tags">

    <a href="/xizhongren8980/tags/" rel="section"><i class="fa fa-tags fa-fw"></i>标签</a>

  </li>
        <li class="menu-item menu-item-categories">

    <a href="/xizhongren8980/categories/" rel="section"><i class="fa fa-th fa-fw"></i>分类</a>

  </li>
        <li class="menu-item menu-item-archives">

    <a href="/xizhongren8980/archives/" rel="section"><i class="fa fa-archive fa-fw"></i>归档</a>

  </li>
      <li class="menu-item menu-item-search">
        <a role="button" class="popup-trigger"><i class="fa fa-search fa-fw"></i>搜索
        </a>
      </li>
  </ul>
</nav>



  <div class="search-pop-overlay">
    <div class="popup search-popup">
        <div class="search-header">
  <span class="search-icon">
    <i class="fa fa-search"></i>
  </span>
  <div class="search-input-container">
    <input autocomplete="off" autocapitalize="off"
           placeholder="搜索..." spellcheck="false"
           type="search" class="search-input">
  </div>
  <span class="popup-btn-close">
    <i class="fa fa-times-circle"></i>
  </span>
</div>
<div id="search-result">
  <div id="no-result">
    <i class="fa fa-spinner fa-pulse fa-5x fa-fw"></i>
  </div>
</div>

    </div>
  </div>

</div>
    </header>

    
  <div class="back-to-top">
    <i class="fa fa-arrow-up"></i>
    <span>0%</span>
  </div>


    <main class="main">
      <div class="main-inner">
        <div class="content-wrap">
          

          <div class="content post posts-expand">
            

    
  
  
  <article itemscope itemtype="http://schema.org/Article" class="post-block" lang="zh-CN">
    <link itemprop="mainEntityOfPage" href="https://gitee.com/xizhongren8980/xizhongren8980.git/2020/04/17/55%E9%A2%98%E4%B9%8B%E8%B7%B3%E8%B7%83%E6%B8%B8%E6%88%8F/">

    <span hidden itemprop="author" itemscope itemtype="http://schema.org/Person">
      <meta itemprop="image" content="/xizhongren8980/images/head.jpg">
      <meta itemprop="name" content="MisterTian">
      <meta itemprop="description" content="一个小菜鸟">
    </span>

    <span hidden itemprop="publisher" itemscope itemtype="http://schema.org/Organization">
      <meta itemprop="name" content="一杯茶一包烟，一个BUG改一天">
    </span>
      <header class="post-header">
        <h1 class="post-title" itemprop="name headline">
          【LeetCode】55题之跳跃游戏
        </h1>

        <div class="post-meta">
            <span class="post-meta-item">
              <span class="post-meta-item-icon">
                <i class="far fa-calendar"></i>
              </span>
              <span class="post-meta-item-text">发表于</span>
              

              <time title="创建时间：2020-04-17 20:22:33 / 修改时间：20:22:19" itemprop="dateCreated datePublished" datetime="2020-04-17T20:22:33+08:00">2020-04-17</time>
            </span>
            <span class="post-meta-item">
              <span class="post-meta-item-icon">
                <i class="far fa-folder"></i>
              </span>
              <span class="post-meta-item-text">分类于</span>
                <span itemprop="about" itemscope itemtype="http://schema.org/Thing">
                  <a href="/xizhongren8980/categories/LeetCode/" itemprop="url" rel="index"><span itemprop="name">LeetCode</span></a>
                </span>
            </span>

          

        </div>
      </header>

    
    
    
    <div class="post-body" itemprop="articleBody">

      
        <h4 id="题目描述"><a href="#题目描述" class="headerlink" title="题目描述:"></a>题目描述:</h4><p>给定一个非负整数数组，你最初位于数组的第一个位置。<a id="more"></a></p>
<p>数组中的每个元素代表你在该位置可以跳跃的最大长度。</p>
<p>判断你是否能够到达最后一个位置。</p>
<h4 id="示例："><a href="#示例：" class="headerlink" title="示例："></a>示例：</h4><p>示例1：</p>
<pre>
输入: [2,3,1,1,4]
输出: true
解释: 我们可以先跳 1 步，从位置 0 到达 位置 1, 
然后再从位置 1 跳 3 步到达最后一个位置。
</pre>

<p>示例2：</p>
<pre>
输入: [3,2,1,0,4]
输出: false
解释: 无论怎样，你总会到达索引为 3 的位置。
但该位置的最大跳跃长度是 0 ， 所以你永远不可能到达最后一个位置。
</pre>


<h4 id="分析："><a href="#分析：" class="headerlink" title="分析："></a>分析：</h4><p>第一想法是从第一个元素开始，每次按照能到达的最大距离进行判断，如果不行就返回，有点类似于回溯。但又仔细想想，题目只是判断能否到达，不需要找到一条最短路径，肯定搞不了这么复杂。再仔细找找每个元素之间的关系，发现可以倒推进行判断，只要当前元素的值大于1，就说明当前元素可以到达身后元素；如果当前元素为0，那么就只需要判断其前一个元素的值是否大于2；因此只需要循环遍历数组一次就能知道结果。</p>
<h4 id="Java实现"><a href="#Java实现" class="headerlink" title="Java实现"></a>Java实现</h4><pre>
<figure class="highlight angelscript"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br><span class="line">16</span><br><span class="line">17</span><br><span class="line">18</span><br></pre></td><td class="code"><pre><span class="line"><span class="keyword">class</span> <span class="symbol">Solution</span> &#123;</span><br><span class="line">    <span class="keyword">public</span> <span class="built_in">bool</span>ean canJump(<span class="built_in">int</span>[] nums) &#123;</span><br><span class="line">        <span class="built_in">int</span> distance = <span class="number">1</span>; <span class="comment">//初始为1是数组倒数第二个与第一个之间的步数</span></span><br><span class="line">        <span class="keyword">for</span>(<span class="built_in">int</span> i = nums.length - <span class="number">2</span>; i &gt;= <span class="number">0</span>; i--)&#123;</span><br><span class="line">            <span class="keyword">if</span>(nums[i] &gt;= distance)&#123;</span><br><span class="line">                <span class="comment">//说明下标为i的元素能够到达其后面一个元素</span></span><br><span class="line">                distance = <span class="number">1</span>;</span><br><span class="line">            &#125;<span class="keyword">else</span>&#123;</span><br><span class="line">                <span class="comment">//说明当前元素无法到达其后面一个元素</span></span><br><span class="line">                distance++; <span class="comment">//用于下一个元素判断</span></span><br><span class="line">            &#125;</span><br><span class="line">            <span class="keyword">if</span> (i == <span class="number">0</span> &amp;&amp; nums[i] &lt; distance)&#123;</span><br><span class="line">                <span class="keyword">return</span> <span class="literal">false</span>;</span><br><span class="line">            &#125;</span><br><span class="line">        &#125;</span><br><span class="line">        <span class="keyword">return</span> <span class="literal">true</span>;</span><br><span class="line">    &#125;</span><br><span class="line">&#125;</span><br></pre></td></tr></table></figure>
</pre>


<h4 id="运行结果："><a href="#运行结果：" class="headerlink" title="运行结果："></a>运行结果：</h4><p><img src="https://gitee.com/xizhongren8980/Hexo_src/raw/master/LeetCode/55_result.png" alt=""></p>
<h4 id="优化："><a href="#优化：" class="headerlink" title="优化："></a>优化：</h4><p>待续……</p>

    </div>

    
    
    

      <footer class="post-footer">
          <div class="post-tags">
              <a href="/xizhongren8980/tags/%E6%95%B0%E7%BB%84/" rel="tag"># 数组</a>
              <a href="/xizhongren8980/tags/%E9%80%86%E5%90%91%E6%80%9D%E7%BB%B4/" rel="tag"># 逆向思维</a>
          </div>

        


        
    <div class="post-nav">
      <div class="post-nav-item">
    <a href="/xizhongren8980/2020/04/16/56%E9%A2%98%E4%B9%8B%E5%90%88%E5%B9%B6%E5%8C%BA%E9%97%B4/" rel="prev" title="【LeetCode】56题之合并区间">
      <i class="fa fa-chevron-left"></i> 【LeetCode】56题之合并区间
    </a></div>
      <div class="post-nav-item">
    <a href="/xizhongren8980/2020/04/20/KMP%E7%AE%97%E6%B3%95/" rel="next" title="KMP算法">
      KMP算法 <i class="fa fa-chevron-right"></i>
    </a></div>
    </div>
      </footer>
    
  </article>
  
  
  



          </div>
          

<script>
  window.addEventListener('tabs:register', () => {
    let { activeClass } = CONFIG.comments;
    if (CONFIG.comments.storage) {
      activeClass = localStorage.getItem('comments_active') || activeClass;
    }
    if (activeClass) {
      let activeTab = document.querySelector(`a[href="#comment-${activeClass}"]`);
      if (activeTab) {
        activeTab.click();
      }
    }
  });
  if (CONFIG.comments.storage) {
    window.addEventListener('tabs:click', event => {
      if (!event.target.matches('.tabs-comment .tab-content .tab-pane')) return;
      let commentClass = event.target.classList[1];
      localStorage.setItem('comments_active', commentClass);
    });
  }
</script>

        </div>
          
  
  <div class="toggle sidebar-toggle">
    <span class="toggle-line toggle-line-first"></span>
    <span class="toggle-line toggle-line-middle"></span>
    <span class="toggle-line toggle-line-last"></span>
  </div>

  <aside class="sidebar">
    <div class="sidebar-inner">

      <ul class="sidebar-nav motion-element">
        <li class="sidebar-nav-toc">
          文章目录
        </li>
        <li class="sidebar-nav-overview">
          站点概览
        </li>
      </ul>

      <!--noindex-->
      <div class="post-toc-wrap sidebar-panel">
          <div class="post-toc motion-element"><ol class="nav"><li class="nav-item nav-level-4"><a class="nav-link" href="#题目描述"><span class="nav-number">1.</span> <span class="nav-text">题目描述:</span></a></li><li class="nav-item nav-level-4"><a class="nav-link" href="#示例："><span class="nav-number">2.</span> <span class="nav-text">示例：</span></a></li><li class="nav-item nav-level-4"><a class="nav-link" href="#分析："><span class="nav-number">3.</span> <span class="nav-text">分析：</span></a></li><li class="nav-item nav-level-4"><a class="nav-link" href="#Java实现"><span class="nav-number">4.</span> <span class="nav-text">Java实现</span></a></li><li class="nav-item nav-level-4"><a class="nav-link" href="#运行结果："><span class="nav-number">5.</span> <span class="nav-text">运行结果：</span></a></li><li class="nav-item nav-level-4"><a class="nav-link" href="#优化："><span class="nav-number">6.</span> <span class="nav-text">优化：</span></a></li></ol></div>
      </div>
      <!--/noindex-->

      <div class="site-overview-wrap sidebar-panel">
        <div class="site-author motion-element" itemprop="author" itemscope itemtype="http://schema.org/Person">
    <img class="site-author-image" itemprop="image" alt="MisterTian"
      src="/xizhongren8980/images/head.jpg">
  <p class="site-author-name" itemprop="name">MisterTian</p>
  <div class="site-description" itemprop="description">一个小菜鸟</div>
</div>
<div class="site-state-wrap motion-element">
  <nav class="site-state">
      <div class="site-state-item site-state-posts">
          <a href="/xizhongren8980/archives/">
        
          <span class="site-state-item-count">57</span>
          <span class="site-state-item-name">日志</span>
        </a>
      </div>
      <div class="site-state-item site-state-categories">
            <a href="/xizhongren8980/categories/">
          
        <span class="site-state-item-count">7</span>
        <span class="site-state-item-name">分类</span></a>
      </div>
      <div class="site-state-item site-state-tags">
            <a href="/xizhongren8980/tags/">
          
        <span class="site-state-item-count">101</span>
        <span class="site-state-item-name">标签</span></a>
      </div>
  </nav>
</div>


  <div class="links-of-blogroll motion-element">
    <div class="links-of-blogroll-title"><i class="fa fa-link fa-fw"></i>
      友情链接
    </div>
    <ul class="links-of-blogroll-list">
        <li class="links-of-blogroll-item">
          <a href="https://mistertian8980.github.io/" title="https:&#x2F;&#x2F;mistertian8980.github.io&#x2F;" rel="noopener" target="_blank">Github博客</a>
        </li>
    </ul>
  </div>

      </div>

    </div>
  </aside>
  <div id="sidebar-dimmer"></div>


      </div>
    </main>

    <footer class="footer">
      <div class="footer-inner">
        

        

<div class="copyright">
  
  &copy; 
  <span itemprop="copyrightYear">2020</span>
  <span class="with-love">
    <i class="fa fa-heart"></i>
  </span>
  <span class="author" itemprop="copyrightHolder">MisterTian</span>
</div>
  <div class="powered-by">由 <a href="https://hexo.io/" class="theme-link" rel="noopener" target="_blank">Hexo</a> & <a href="https://theme-next.org/" class="theme-link" rel="noopener" target="_blank">NexT.Gemini</a> 强力驱动
  </div>

        








      </div>
    </footer>
  </div>

  
  <script size="300" alpha="0.6" zIndex="-1" src="/xizhongren8980/lib/canvas-ribbon/canvas-ribbon.js"></script>
  <script src="/xizhongren8980/lib/anime.min.js"></script>
  <script src="/xizhongren8980/lib/velocity/velocity.min.js"></script>
  <script src="/xizhongren8980/lib/velocity/velocity.ui.min.js"></script>

<script src="/xizhongren8980/js/utils.js"></script>

<script src="/xizhongren8980/js/motion.js"></script>


<script src="/xizhongren8980/js/schemes/pisces.js"></script>


<script src="/xizhongren8980/js/next-boot.js"></script>


  <script defer src="//cdn.jsdelivr.net/gh/theme-next/theme-next-three@1/three.min.js"></script>
    <script defer src="//cdn.jsdelivr.net/gh/theme-next/theme-next-three@1/canvas_lines.min.js"></script>


  




  
<script src="/xizhongren8980/js/local-search.js"></script>













  

  

</body>
</html>
